| Message ID | 20230821-fix-ti-sysc-reset-v1-1-5a0a5d8fae55@baylibre.com |
|---|---|
| State | New |
| Headers | show |
| Series | bus: ti-sysc: Use fsleep() instead of usleep_range() in sysc_reset() | expand |
* Tony Lindgren <tony@atomide.com> [230822 09:27]: > * Julien Panis <jpanis@baylibre.com> [230821 14:24]: > > The am335x-evm started producing boot errors because of subtle timing > > changes: > > > > Unhandled fault: external abort on non-linefetch (0x1008) at 0xf03c1010 > > ... > > sysc_reset from sysc_probe+0xf60/0x1514 > > sysc_probe from platform_probe+0x5c/0xbc > > ... > > > > The fix consists in using the appropriate sleep function in sysc reset. > > For flexible sleeping, fsleep is recommended. Here, sysc delay parameter > > can take any value in [0 - 255] us range. As a result, fsleep() should > > be used, calling udelay() for a sysc delay lower than 10 us. > > > > Signed-off-by: Julien Panis <jpanis@baylibre.com> > > Fixes: e709ed70d122 ("bus: ti-sysc: Fix missing reset delay handling") > > --- > > Fix boot errors for am335x-evm in sysc_reset(), by using fsleep() instead > > of usleep_range() function. Thus, udelay() will be called if the configured > > sysc delay is lower than 10 us (which is usually the case, since the value > > set in the device tree is currently 2 us). > > OK, interesting. Yeah I've only ever seen values of 2 us needed here. Applied into fixes thanks Tony
diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c index 4cb23b9e06ea..59b8bdd9203e 100644 --- a/drivers/bus/ti-sysc.c +++ b/drivers/bus/ti-sysc.c @@ -2147,8 +2147,7 @@ static int sysc_reset(struct sysc *ddata) } if (ddata->cfg.srst_udelay) - usleep_range(ddata->cfg.srst_udelay, - ddata->cfg.srst_udelay * 2); + fsleep(ddata->cfg.srst_udelay); if (ddata->post_reset_quirk) ddata->post_reset_quirk(ddata);
The am335x-evm started producing boot errors because of subtle timing changes: Unhandled fault: external abort on non-linefetch (0x1008) at 0xf03c1010 ... sysc_reset from sysc_probe+0xf60/0x1514 sysc_probe from platform_probe+0x5c/0xbc ... The fix consists in using the appropriate sleep function in sysc reset. For flexible sleeping, fsleep is recommended. Here, sysc delay parameter can take any value in [0 - 255] us range. As a result, fsleep() should be used, calling udelay() for a sysc delay lower than 10 us. Signed-off-by: Julien Panis <jpanis@baylibre.com> Fixes: e709ed70d122 ("bus: ti-sysc: Fix missing reset delay handling") --- Fix boot errors for am335x-evm in sysc_reset(), by using fsleep() instead of usleep_range() function. Thus, udelay() will be called if the configured sysc delay is lower than 10 us (which is usually the case, since the value set in the device tree is currently 2 us). --- drivers/bus/ti-sysc.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- base-commit: f7757129e3dea336c407551c98f50057c22bb266 change-id: 20230821-fix-ti-sysc-reset-5c164051345b Best regards,